JP5325202B2 - Solid-state imaging device, manufacturing method thereof, and electronic information device - Google Patents

Abstract

A solid-state image capturing element having light receiving parts which are each shared by a plurality of pixels and approach each other, wherein the light receiving sensitivity and shading are further improved. A light pipe (10) which has a parallelogram-shaped cross section and constitutes an optical waveguide is formed in an interlayer insulation film (9) between a microlens (14) and a light receiving part (3), the lower end surface of the light pipe (10) is open at a position above the light receiving part (3) so as to include the middle of the light receiving part (3) in plan view, the upper end surface thereof is open at a position below the microlens (14) so as to include the middle of the microlens (14) in plan view, and the regions of the upper and lower end surfaces are displaced and different from each other in plan view.

Description

  The present invention relates to a solid-state imaging device such as a CCD image sensor or a CMOS image sensor in which a plurality of light-receiving units that photoelectrically convert image light from a subject and image it, a manufacturing method thereof, and a solid-state imaging device. Electronic cameras such as digital video cameras and digital still cameras used as image input devices, such as digital video cameras and digital still cameras, image input cameras such as surveillance cameras, scanner devices, facsimile devices, television telephone devices, camera-equipped mobile phone devices, etc. It relates to information equipment.

  A conventional CCD image sensor or CMOS having a two-pixel sharing, which has a two-pixel sharing transfer unit, and the positions of the light-receiving units that photoelectrically convert the image light from the subject to image each other in two-pixel units are periodically different. Image sensors are proposed in Patent Documents 1-5.

  FIG. 6 is a longitudinal sectional view schematically showing an example of the configuration of the main part of a conventional CCD image sensor disclosed in Patent Document 1. As shown in FIG.

  As shown in FIG. 6, in a conventional CCD image sensor 100, a plurality of light receiving units 102 that photoelectrically convert image light from a subject on a semiconductor substrate 101 are arranged in a two-dimensional manner by approaching each other in units of two pixels. The charge transfer unit 103 is provided adjacent to the light receiving unit 102. A gate electrode 104 is provided on the charge transfer portion 103, and a light shielding film 106 is provided thereon via an insulating film 105. A transparent interlayer snow surface film 107 is provided so as to fill a step between the upper surface of the light receiving unit 102 and the light shielding film 106. A flattening film 108 is provided on the interlayer snow film 107, a color filter 109 is provided in a predetermined color arrangement on the flattening film 108, and a flattening film 110 is provided on the color filter 109. On the planarizing film 110, a convex transparent portion 111 is provided so as to cover these two pixels that are close to each other, and two microlenses 112 are provided on the planarizing film 110 so as to correspond to the light receiving portions 102, respectively. Yes. Due to the inclination of the convex transparent portion 111, the direction of the incident light is bent toward each light receiving portion 102 in units of two pixels, and is easily incident on each light receiving portion 102.

  FIG. 7 is a longitudinal sectional view schematically showing an example of the configuration of the main part of a conventional CMOS image sensor disclosed in Patent Document 2. As shown in FIG.

  As shown in FIG. 7, a conventional CMOS image sensor 200 includes a light receiving unit 201 that receives light and converts it into electric charges, a microlens 202 that collects incident light on the light receiving unit 201, and a light receiving unit 201. And the microlens 202 are provided with an interlayer insulating film 203 and a protective film 204, and the interlayer insulating 203 and the protective film 204 are made of light transmitting materials having different refractive indexes. The interface between the interlayer insulating film 203 and the protective film 204 is formed so as to have an inclination corresponding to the amount of deviation of the planar position between the light receiving unit 201 and the microlens 202. Reference numeral 205 denotes a color filter, and 206 denotes a metal wiring.

  Next, in the conventional two-pixel sharing solid-state imaging device disclosed in Patent Documents 3 to 5, the microlenses are formed so as to stick to each other in a two-pixel cycle and one end portion overlaps each other.

JP 2002-270811 A JP 2005-150492 A JP 2007-95751 A JP 2007-208817 A JP 2007-311413 A

  In the conventional technique disclosed in Patent Document 1, since the cross-sectional shape of the micro lens 112 provided on the convex transparent portion 111 is inclined at a period of two pixels, the micro lens 112 is microscopic with respect to parallel light from directly above. Even when the lens 112 is optimized so that the incident light on each adjacent light receiving unit 102 is condensed on the central portion of the light receiving unit 102, the oblique light is received by each adjacent light receiving unit 102. There is a problem that incident light is not condensed at the center. That is, when, for example, oblique light inclined in the direction from the upper left to the lower right is incident on the two left and right micro lenses 112 inclined in opposite directions, the left micro lens 112 has a right micro lens. The light receiving efficiency at the light receiving unit 102 is higher than that of the lens 112 and the light receiving sensitivity is good. This is because, for example, in the conventional techniques disclosed in Patent Documents 3 to 5 in which the left and right microlenses are attached to each other with a period of two pixels, oblique light inclined from the upper left to the lower right is used. When incident, the left microlens has better light receiving efficiency at the light receiving section and better light receiving sensitivity than the right microlens. Therefore, in the conventional techniques disclosed in Patent Documents 1 and 3 to 5, there is a problem that the light receiving sensitivity and shading in the light receiving unit 102 that is periodically shifted by 2 pixels with respect to the oblique light are deteriorated.

  Further, in the conventional technique disclosed in Patent Document 2, the interface between the interlayer insulating film 203 and the protective film 204 is in accordance with the amount of displacement of the planar position between each light receiving unit 201 and the microlens 202 sharing two pixels. Although it is formed so as to have an inclination, since the condensing direction from the microlens 202 is adjusted with an inclined surface even for oblique light, each central part of the light receiving parts 201 that are close to each other and share two pixels. Therefore, it is difficult to adjust the inclined surface so as to bend the condensed light stably and accurately.

  The present invention solves the above-described conventional problems, and in a solid-state imaging device having a plurality of pixel-sharing light-receiving portions close to each other, the solid-state imaging device capable of further improving the light receiving sensitivity and shading, and a method for manufacturing the same An object of the present invention is to provide an electronic information device such as a mobile phone device with a camera using a solid-state imaging device as an image input device in an imaging unit.

In the solid-state imaging device of the present invention, a plurality of light receiving units that photoelectrically convert incident light to generate signal charges are arranged two-dimensionally, and a plurality of light collecting units that collect the incident light on each of the plurality of light receiving units. In a solid-state imaging device in which a microlens is disposed above the plurality of light receiving portions, a light pipe constituting an optical waveguide is formed in an interlayer insulating film between the microlens and the light receiving portion, and the light pipe Is formed so as to have an oblique cross section, and has a lower end surface opened at a position above the light receiving portion so as to include the central portion of the light receiving portion in plan view, and an upper end surface at the lower position of the micro lens in plan view. Opening so as to include the center of the microlens, the upper and lower end face regions are different from each other in plan view , and the vertical cross-sectional shape of the light pipe is a parallelogram shape or an inverted right trapezoid shape, thereby The above objective is achieved.

  Preferably, in the solid-state image pickup device of the present invention in which the planar view position of the light-receiving unit in the solid-state image pickup device is periodically different, according to the position of the light-receiving unit periodically shifted in units of the plurality of pixels. Thus, the plan view position of the lower end surface of the light pipe is positioned.

  Further preferably, the plurality of microlenses in the solid-state imaging device of the present invention and the upper end surfaces of the light pipes corresponding to the plurality of microlenses are all formed at equal intervals.

More preferably, the material of the light pipe in the solid-state imaging device of the present invention is a high refractive index film such as a SiN film or a SiON film, and the interlayer insulating film is a SiO ₂ film.

  Further, preferably, at least one of the upper end surface and the lower end surface of the light pipe in the solid-state imaging device of the present invention is a circle, an ellipse, or a quadrangle including a square or a rectangle in plan view.

  Further, preferably, the upper and lower end surface regions in the solid-state imaging device of the present invention are included in each other in a plan view or are shifted from each other in a plan view.

  Further preferably, in the solid-state imaging device of the present invention, an in-layer lens for further condensing light from the microlens is provided on or above the light pipe.

  Further preferably, in the solid-state imaging device of the present invention, the light receiving unit is provided as a photoelectric conversion unit for each pixel, and the signal charge from the light receiving unit is transferred in a predetermined direction adjacent to the light receiving unit. A charge transfer unit, and a gate electrode for controlling the charge transfer of the read signal charges, and a light shielding film disposed thereon, and the light shielding film is opened above the light receiving unit. And a CCD solid-state imaging device in which the interlayer insulating film is formed so as to bury a step between the portion and the light shielding film on the gate electrode.

  Further preferably, in the solid-state imaging device of the present invention, the light receiving unit is provided as a photoelectric conversion unit for each pixel, and the signal charge from the light receiving unit is transferred to the charge voltage conversion unit adjacent to the light receiving unit. A charge transfer transistor for performing a signal conversion, and a signal charge transferred to the charge voltage conversion unit by the charge transfer transistor for each light receiving unit is converted into a voltage, and is amplified in accordance with the conversion voltage and imaged for each pixel unit A readout circuit for reading out as a signal, and a CMOS solid-state imaging device in which the charge transfer transistor and the transistor constituting the readout circuit and the interlayer insulating film are formed on the light receiving portion.

  The method for manufacturing a solid-state imaging device according to the present invention is a method for manufacturing the solid-state imaging device according to the present invention, wherein a transparent interlayer insulating film between the microlens and the light receiving unit is provided at a lower center of the microlens. And a light pipe forming step of forming a light pipe constituting an optical waveguide that opens to the upper portion of the light receiving portion in plan view, thereby achieving the above object.

  Preferably, in the method for manufacturing a solid-state imaging device of the present invention, an intra-layer lens for forming an intra-layer lens on the light pipe for further condensing light from the microlens into the light pipe. It further has a forming step.

  Preferably, in the light pipe forming step in the method of manufacturing a solid-state imaging device according to the present invention, the first resist film is formed in a predetermined shape on the transparent interlayer insulating film between the microlens and the light receiving portion by photolithography. The first resist film forming step for patterning and using the patterned first resist film as a mask, the interlayer insulating film is etched to a predetermined depth so that the side surface is tapered, and the taper is opened upward. A photolithographic technique so as to cover the first recess forming step for forming the first recess, the step of filling the first recess with a transparent high refractive index film, and the high refractive index film embedded in the first recess. And a second resist film forming step of patterning the second resist film into a predetermined shape, and using the patterned second resist film as a mask, the high refractive index film has a side taper A second recess forming step of forming a second recess which is etched to a predetermined depth and opened upward in a tapered shape, and the second recess is filled with the same material as the material of the interlayer insulating film. Forming a parallelogram light pipe.

  Further preferably, in the light pipe forming step in the method for manufacturing a solid-state imaging device of the present invention, the first resist film is formed in a predetermined shape on the transparent interlayer insulating film between the microlens and the light receiving portion by photolithography. The first resist film forming step for patterning and using the patterned first resist film as a mask, the interlayer insulating film is etched to a predetermined depth so that the side surface is tapered, and the taper is opened upward. A photolithographic technique so as to cover the first recess forming step for forming the first recess, the step of filling the first recess with a transparent high refractive index film, and the high refractive index film embedded in the first recess. And a third resist film forming step of patterning the third resist film into a predetermined shape, and using the patterned third resist film as a mask, the side surface is perpendicular to the high refractive index film. A third recess forming step of forming a third recess that is vertically etched upward to a predetermined depth so as to stand up, and the third recess is filled with the same material as the material of the interlayer insulating film to have a cross-sectional shape Forming an inverted right trapezoidal light pipe.

  Further preferably, the light pipe forming step in the method of manufacturing a solid-state imaging device according to the present invention includes forming the first light pipe on the transparent interlayer insulating film between the microlens and the light receiving unit by photolithography. A fourth resist film forming step of obtaining a fourth resist film by patterning the resist film into a predetermined shape in a state where the side wall of the opening corresponding to the position is tapered, and the interlayer along with the patterned fourth resist film Etching the insulating film to transfer the tapered shape of the side surface of the opening of the fourth resist film to the interlayer insulating film to form a fourth recessed portion opened upward in a tapered shape; A step of embedding the concave portion with a transparent high refractive index material film, and a second light pipe forming position on the high refractive index material film and the interlayer insulating film by photolithography. A fifth resist film forming step of obtaining a fifth resist film by patterning the resist film in a predetermined shape with the side wall of the corresponding opening tapered, and the high refraction along with the patterned fifth resist film Etching the refractive index material film transfers the tapered shape of the side surface of the opening of the fifth resist film to the high refractive index material film, thereby forming a fifth concave portion that opens upward in a tapered shape. And a method of manufacturing a solid-state imaging device, in which the same material as that of the interlayer insulating film is embedded in the fifth recess to form two light pipes on the left and right.

  Further preferably, in the intralayer lens forming step in the method for manufacturing a solid-state imaging device of the present invention, a high refractive index material film is formed on or above at least the light pipe of the light pipe and the interlayer insulating film. A step of forming a high refractive index material film, forming a photosensitive resist film on the high refractive index material film, and controlling the amount of irradiation light using a transmittance gradation mask to form the photosensitive resist film; A resist lens shape forming step for forming a lens shape, and the same high refraction reflecting the lens shape of the photosensitive resist film by simultaneously etching the photosensitive resist film and the high refractive index material film of the lens shape A high-refractive-index material film lens shape forming step for forming the refractive-index material film into a lens shape.

  Further preferably, in the intralayer lens forming step in the method for manufacturing a solid-state imaging device of the present invention, a high refractive index material film is formed on or above at least the light pipe of the light pipe and the interlayer insulating film. A high refractive index material film forming step, a resist film forming step of forming a photosensitive resist film on the high refractive index material film, and patterning the resist film into a predetermined shape by lithography technology, and reflowing the patterned resist film Then, a resist lens shape forming step for forming an upward convex lens shape by the surface tension, and the lens-shaped resist film and the high refractive index material film are simultaneously etched to reflect the lens shape of the resist film. And a lens shape forming step for forming the high refractive index material film having the same lens shape.

  The electronic information device of the present invention uses the solid-state imaging device of the present invention as an image input device in an imaging unit, and thereby achieves the above object.

  With the above configuration, the operation of the present invention will be described below.

  In the present invention, a light pipe that constitutes an optical waveguide is formed in an interlayer insulating film between the microlens and the light receiving unit, and the light pipe has a lower end surface at a position above the light receiving unit and a center of the light receiving unit in plan view. The upper end surface is opened at a position below the microlens so as to include the central portion of the microlens in plan view, and the upper and lower end surface regions are different from each other in plan view.

  Thereby, it is possible to further improve the light receiving sensitivity and shading in the solid-state imaging device having the light receiving portions that are shared by a plurality of pixels.

  As described above, according to the present invention, in the solid-state image pickup device sharing a plurality of pixels in which the positions of the light receiving portions are periodically different, the light pipe is oblique in cross section according to the positions of the light receiving portions that are periodically shifted due to the sharing of the plurality of pixels. Since the lower end of the light pipe is open above the central part of the light receiving part and the upper end of the light pipe is open below the central part of the microlens, By periodically shifting the position of the light receiving unit, even if the planar view position of the light receiving unit and the microlens is shifted, it can be accurately and reliably condensed at the center position of each light receiving unit by the light pipe, The light receiving sensitivity and shading can be further improved. In this case, since the microlens and the upper end portion of the light pipe are formed at equal intervals, it is possible to make the incident light amount to each adjacent light receiving portion close to each other by sharing a plurality of pixels and to make each light receiving portion the same. Thus, variations in the amount of incident light can be eliminated.

It is a longitudinal cross-sectional view which shows typically the principal part structural example of the CCD solid-state image sensor in Embodiment 1 of this invention. It is a principal part longitudinal cross-sectional view for demonstrating the light pipe formation process in the manufacturing method of the CCD solid-state image sensor of FIG. It is a longitudinal cross-sectional view which shows typically the example of a principal part structure of the CCD solid-state image sensor in Embodiment 2 of this invention. It is a principal part longitudinal cross-sectional view for demonstrating the light pipe formation process in the manufacturing method of the CCD solid-state image sensor of FIG. As Embodiment 4 of this invention, it is a block diagram which shows the schematic structural example of the electronic information apparatus which used the solid-state image sensor 1 or 1A or 1B of Embodiments 1-3 of this invention for the imaging part. It is a longitudinal cross-sectional view which shows typically the example of a principal part structure of the conventional CCD image sensor currently disclosed by patent document 1. FIG. It is a longitudinal cross-sectional view which shows typically the example of a principal part structure of the conventional CMOS image sensor currently disclosed by patent document 2. FIG. It is a longitudinal cross-sectional view which shows typically the example of a principal part structure of the CCD solid-state image sensor in Embodiment 3 of this invention. (A)-(e) is a principal part longitudinal cross-sectional view for demonstrating the light pipe formation process in the manufacturing method of the CCD solid-state image sensor of FIG.

  Hereinafter, Embodiments 1 to 3 of the solid-state imaging device and the manufacturing method thereof according to the present invention and, for example, a camera-equipped mobile phone apparatus using any of Embodiments 1 to 3 of the solid-state imaging device as an image input device in an imaging unit Embodiment 4 of an electronic information device such as the above will be described in detail with reference to the drawings. In addition, each thickness, length, etc. of the structural member in each figure are not limited to the structure to illustrate from a viewpoint on drawing preparation.

(Embodiment 1)
FIG. 1 is a longitudinal sectional view schematically showing an example of the configuration of the main part of a CCD solid-state imaging device according to Embodiment 1 of the present invention.

  In FIG. 1, the CCD solid-state imaging device 1 according to the first embodiment has a charge transfer unit 4 sharing two pixels, and the arrangement positions are different so that the positions of a plurality of pixel units are periodically shifted from each other in units of two pixels. ing. Each pixel portion is provided with a plurality of two-dimensional light receiving portions 3 formed of photodiodes that generate signal charges by photoelectrically converting incident light as light receiving elements on the surface portion of the semiconductor substrate 2. A charge transfer unit 4 is provided adjacent to the unit 3 for reading and transferring the signal charge from the light receiving unit 3 through the signal charge reading unit. A gate electrode 6 is disposed on the charge transfer unit 4 and the signal charge readout unit with a gate insulating film 5 interposed therebetween. The gate electrode 6 functions as a charge transfer electrode for reading out signal charges and controlling charge transfer of the read signal charges in a predetermined direction.

  On the gate electrode 6, a light shielding film 7 is formed via an insulating layer 8 in order to prevent incident light from being reflected by the gate electrode 6 and generating noise. Further, above the light receiving portion 3, an opening 7 a is formed in the light shielding film 7 as a window portion for incident light.

An interlayer insulating film 9 for flattening the stepped portion between the surface of the light receiving portion 3 and the light shielding film 7 is formed. This interlayer insulating film 9 is a transparent SiO ₂ film. The interlayer insulating film 9 is opened so that the lower end surface includes a central portion of the light receiving unit 3 in a plan view above the light receiving unit 3, and the upper end surface is viewed in a plan view below a microlens 14 described later. The light pipe 10 is formed so as to include the central portion of the microlens 14 and constitute an optical waveguide in which upper and lower end face regions are different from each other in plan view.

  Further, a planarizing film 11 is formed on the upper end surfaces of the interlayer insulating film 9 and the light pipe 10, and predetermined colors of R, G, and B colors arranged for each light receiving unit 3 on the planarizing film 11. An array (for example, a Bayer array) of color filters 12 is formed. Further, a planarizing film 13 is formed on the color filter 12, and a microlens 14 for condensing light to the light receiving unit 3 is formed thereon.

  The light pipe 10 is formed obliquely in the depth direction so that the upper and lower positions thereof are different. The plan view shape of the lower end surface of the light pipe 10 is circular, elliptical, quadrangular, or the like, and is opened above the light receiving unit 3 so as to include the central portion in plan view. The plan view shape of the upper end surface of the light pipe 10 is also a circle, an ellipse, a quadrangular shape, and the like, and is opened below the microlens 14 so as to include the central portion in the plan view. As a result, incident light, including oblique light, is condensed inside the upper end surface region of the light pipe 10 by the microlens 14, and is emitted from the lower end surface of the light pipe 10 through the light pipe 10 to be centered in the light receiving unit 3. Is incident on the part. As a result, the degree of freedom in designing the arrangement of the microlenses 14 is increased, and it is not necessary to provide the microlenses 14 directly above the light receiving unit 3.

  As a manufacturing method of the CCD solid-state imaging device 1 according to the first embodiment having the above-described configuration, a plurality of light receiving units 3 that photoelectrically convert incident light to form an image on a semiconductor substrate 2 (or a semiconductor layer) are two-dimensionally formed. A light receiving portion forming step, a charge transfer portion forming step for forming a charge transfer portion 4 as a charge transfer portion and a gate electrode 6 thereon adjacent to each light receiving portion 3, and covering the gate electrode 6; A light shielding film forming step of forming a light shielding film 7 opened above the light receiving portion 3; an interlayer insulating film forming step of forming a transparent interlayer insulating film 9 on the step portions of the light receiving portion 3 and the light shielding film 7; A light pipe forming step for forming a light pipe that forms an optical waveguide that opens in the lower central portion of the microlens 14 and opens upward in the central portion in plan view of the light receiving portion 3; And light pie A color filter forming step of forming a color filter 12 of a predetermined color arrangement corresponding to the position of each light receiving portion 3 on the color filter 12 via the flattening film 11, and a flattening film 13 on the color filter 12. And a microlens forming step for forming the microlens 14 corresponding to the position of each light receiving portion 3.

In this light pipe forming step, first, a resist film (not shown) is opened in a predetermined shape in a transparent SiO ₂ film that is a material of the interlayer insulating film 9 so that the side surface is tapered, and this is masked. Etching is performed for a predetermined plan view shape and a predetermined depth. Next, this etching shape is formed in a concave portion opened upward in a tapered shape with a cross-sectional shape in which a trapezoid is turned upside down. The recess is filled with a transparent SiN film of a high refractive index material film (high refractive index film). Subsequently, as shown in FIG. 2, a resist film 21 is opened in a predetermined shape and patterned in the SiN film embedded in the recess so that the side surface is tapered, and the patterned resist film 21 is masked. Etching to a predetermined plan view shape and a predetermined depth (the same depth as the initial depth). An etching stopper film may be provided on the bottom of the recess. This etching shape (concave shape) is smaller than the initial etching shape (concave shape), and is formed in a concave portion having a cross-sectional shape in which the trapezoid is turned upside down in the initial etching shape region. Two light pipes 10 each having a parallelogram cross section can be formed by filling the recess with a transparent SiO ₂ film 9a. The material of the light pipe 10 may be a SiON film in addition to the high refractive index material SiN film. This SiO ₂ film 9 a can be made of the same film material as that of the transparent SiO ₂ film constituting the interlayer insulating film 9.

  In short, this light pipe forming step includes a first resist film forming step of patterning a first resist film into a predetermined shape by a photolithography technique on the transparent interlayer insulating film 9 between the microlens 14 and the light receiving unit 3; Using the patterned first resist film as a mask, a first recess forming step is formed in the interlayer insulating film 9 by etching to a predetermined depth so that the side surface is tapered to open a first recess that is tapered upward. And a step of embedding the first concave portion with a transparent high refractive index material film and a second resist film (resist film 21) by photolithography so as to cover the high refractive index material film embedded in the first concave portion. A second resist film forming step of patterning into a predetermined shape, and a predetermined pattern so that the side surface of the high refractive index material film is tapered using the patterned second resist film as a mask A second recess forming step for forming a second recess that is etched upward to open in a tapered shape, and the second recess is filled with the same material as the material of the interlayer insulating film 9 and inclined obliquely in a parallelogram shape in cross section. And an embedding process for forming two light pipes.

  As described above, according to the first embodiment, the light pipe 10 having a parallelogram-shaped cross section constituting the optical waveguide is formed in the interlayer insulating film 9 between the microlens 14 and the light receiving unit 3. The end surface opens at a position above the light receiving portion 3 so as to include the central portion of the light receiving portion 3 in plan view, and the upper end surface opens at a position below the micro lens 14 so as to include the central portion of the micro lens 14 in plan view. Thus, the upper and lower end face regions are different from each other in plan view.

  As a result, in the solid-state imaging device 1 sharing two pixels in which the positions of the light receiving portions 3 are periodically different, the light pipe 10 is inclined in the cross-sectional direction according to the positions of the light receiving portions 3 that are periodically shifted in units of two pixels. Since the lower end surface portion of the light pipe 10 is located above the center portion of the light receiving portion 3 and the upper end surface portion of the light pipe 10 is located below the center portion of the microlens 14. Since the positions of the adjacent light receiving units 3 that share two pixels are periodically shifted, light is guided by the light pipe 10 even when the positions of the light receiving unit 3 and the microlens 14 are shifted in plan view. The light can be condensed accurately and reliably at the center position of each light receiving unit 3, and the light receiving sensitivity and shading can be further improved. In this case, since the microlens 14 and the upper end surface portion of the light pipe 10 are formed at equal intervals, it is possible to make the incident light amounts to the adjacent light receiving portions 3 close to each other by sharing two pixels. Variations in the amount of incident light can be eliminated in each light receiving unit 3.

(Embodiment 2)
In the first embodiment, the case where the cross-sectional shape of the light pipe 10 is formed in a parallelogram shape has been described. In the second embodiment, the case where the cross-sectional shape of the light pipe 10 is formed in an inverted right-angled trapezoid shape will be described.

  FIG. 3 is a longitudinal sectional view schematically showing an example of the configuration of the main part of a CCD solid-state imaging device according to Embodiment 2 of the present invention. In FIG. 3, the same reference numerals are given to the constituent members having the same functions and effects as the constituent members of the CCD solid-state imaging device 1 in FIG. 1, and description thereof is omitted.

  In FIG. 3, the CCD solid-state imaging device 1 </ b> A of the second embodiment is different from the CCD solid-state imaging device 1 of the first embodiment in that the vertical cross-sectional shape of the light pipe 10 a is configured in an inverted right trapezoid shape. is there.

  The light pipe 10a is formed in an inverted right-angled trapezoidal shape with one side surface inclined and the other side surface vertical in the depth direction so that the upper position area includes the lower position area. The plan view shape of the lower end surface of the light pipe 10a is a circle, an ellipse, a quadrangle, or the like, and is opened above the light receiving unit 3 so as to include the central portion in plan view. The opening area of the lower end surface of the light pipe 10a has the same shape and area as the opening area of the lower end surface of the light pipe 10 of the first embodiment. Moreover, the planar view shape of the upper end surface of the light pipe 10a is also a circle, an ellipse, a quadrangle, or the like, and is opened below the microlens 14 so as to include the central portion in the planar view. The opening area of the upper end face of the light pipe 10a is wide including the area of the upper end face of the light pipe 10 of the first embodiment. As a result, incident light, including oblique light, is condensed inside the wide upper end surface region of the light pipe 10a by the microlens 14, and is emitted from the lower end surface of the light pipe 10a through the light pipe 10a. Incidently enter the center. As a result, the degree of freedom in designing the arrangement of the microlenses 14 is increased, and it is not necessary to provide the microlenses 14 directly above the light receiving unit 3.

In the light pipe forming step in the manufacturing method of the CCD solid-state imaging device 1A of the second embodiment having the above-described configuration, first, a resist is formed on a transparent SiO ₂ film that is a material of the interlayer insulating film 9 so that the side surface is tapered. The film is opened and patterned in a predetermined shape, and this is used as a mask to etch the film in a predetermined shape and a predetermined depth. An etching stopper film may be provided on the bottom. Next, this etching shape (recess cross-sectional shape) is a recess having a cross-sectional shape in which the trapezoid is turned upside down, and is formed in a recess opened upward in a tapered shape. The recess is filled with a transparent high refractive index material SiN film. Subsequently, as shown in FIG. 4, the resist film 22 is opened in a predetermined shape and patterned in the SiN film embedded in the recess, and the side surface is etched by using this as a mask to a predetermined shape and a predetermined depth. Vertical recesses (recesses with sharp side faces) are formed. This etching residual shape is formed in a trapezoidal shape with a right-angle cross section in which the portion of the remaining SiN film in the first etching shape region is trapezoidal upside down. Two light pipes 10a can be formed on the left and right sides by filling the etched recesses with a transparent SiO ₂ film 9a. The material of the light pipe 10a may be a SiON film in addition to the high refractive index material SiN film. The SiO ₂ film 9 a is made of the same film material as that of the transparent SiO ₂ film constituting the interlayer insulating film 9.

  In short, this light pipe forming step includes a first resist film forming step of patterning a first resist film into a predetermined shape by a photolithography technique on the transparent interlayer insulating film 9 between the microlens 14 and the light receiving unit 3; Using the patterned first resist film as a mask, a first recess forming step is formed in the interlayer insulating film 9 by etching to a predetermined depth so that the side surface is tapered to open a first recess that is tapered upward. And a step of filling the first recess with a transparent high refractive index material film, and a third resist film (resist film 22) by photolithography so as to cover the high refractive index material film embedded in the first recess. A third resist film forming step for patterning into a predetermined shape, and a predetermined depth so that the side surfaces of the high-refractive index material film are vertically cut using the patterned third resist film as a mask. A third recess forming step for forming a third recess that is vertically opened upward by etching, and a light pipe 10a having an inverted right-angled trapezoidal cross section with the same material as the interlayer insulating film embedded in the third recess. And a burying step of forming

  As described above, according to the second embodiment, the light pipe 10a having the inverted right-angled trapezoidal cross section forming the optical waveguide is formed in the interlayer insulating film 9 between the microlens 14 and the light receiving unit 3, and the light pipe 10a. The lower end surface opens so as to include the central portion of the light receiving portion 3 in a plan view above the light receiving portion 3, and the upper end surface includes the central portion of the micro lens 14 in a plan view below the micro lens 14. The upper and lower end face regions are included in the plan view.

  Thus, in the two-pixel shared CCD solid-state imaging device 1A in which the positions of the light receiving portions 3 are periodically different, the light pipe 10a is oblique in cross section according to the positions of the light receiving portions 3 that are periodically shifted in units of two pixels. The lower end surface of the light pipe 10a is opened above the center of the light receiving unit 3 and the upper end surface of the light pipe 10a is below the center of the microlens 14. However, since the opening is positioned so as to collect light more widely than in the case of the first embodiment, the positions of the adjacent light receiving units 3 that share two pixels are periodically shifted, so Even if the position of the lens 14 is shifted in plan view, the light pipe 10a can guide the light to the light receiving unit 3 side and accurately focus the light on the center position of each light receiving unit 3. Shi It is possible to further improve the over loading. In this case, the plurality of microlenses 14 and the upper end surfaces of the light pipes 10a corresponding to the plurality of microlenses 14 are all formed at equal intervals. Thus, since the microlens 14 and the upper end surface portion of the light pipe 10a are formed at equal intervals, the amount of incident light on each adjacent light receiving portion 3 can be made the same by sharing two pixels. Thus, it is possible to eliminate variations in the amount of incident light at each light receiving unit 3.

(Embodiment 3)
In the third embodiment, a case where an intralayer lens is provided on the light pipe 10b similar to the light pipe 10 of the first embodiment, and the light from the microlens 14 is more reliably guided into the light pipe 10b will be described. To do.

  FIG. 8 is a longitudinal sectional view schematically showing an example of the configuration of the main part of a CCD solid-state imaging device according to Embodiment 3 of the present invention. In FIG. 8, the same reference numerals are given to the constituent members having the same functions and effects as the constituent members of the CCD solid-state imaging device 1 in FIG. 1, and description thereof is omitted.

  In FIG. 8, the CCD solid-state imaging device 1B of the third embodiment is different from the CCD solid-state imaging device 1 of the first embodiment in that a light pipe 10b that guides light in an oblique direction is formed in the interlayer insulating film 9, This is the point that an in-layer lens 15 is provided on the light pipe 10b to more reliably guide the light collected from the microlens 14 into the light pipe 10b. A flattening film 11A is formed on the interlayer insulating film 9 and the inner lens 15 so as to bury them and flatten the upper surface.

  As in the case of the light pipe 10 of the first embodiment, the light pipe 10b is formed obliquely in the depth direction so that the upper and lower positions thereof are different. The plan view shape of the lower end surface of the light pipe 10b is a circle, an ellipse, a quadrangle, or the like, and is opened above the light receiving unit 3 so as to include the central portion in plan view. The plan view shape of the upper end surface of the light pipe 10b is also a circle, an ellipse, a quadrangle, or the like, and is open below the micro lens 14 so as to include the central portion in plan view.

  An in-layer lens 15 is provided directly on the light pipe 10b, and the in-layer lens 15 condenses in the light pipe 10b to guide light. As a result, the incident light including the oblique light is condensed on the inner lens 15 by the microlens 14, and further collected by the inner lens 15 inside the upper end surface region of the light pipe 10b, and then in the light pipe 10b. Then, the light is guided in an oblique direction on the light receiving unit 3 side, is emitted from the lower end surface of the light pipe 10 b, and enters the center of the light receiving unit 3. As described above, by further providing the inner lens 15 between the microlens 14 and the light pipe 10b, the degree of freedom in the arrangement design of the microlens 14 is further increased, and the microlens 14 is placed directly above the light receiving unit 3. There is no longer any need to provide it. Further, the light condensing from the microlens 14 can be more reliably condensed on the center of the light receiving unit 3 via the inner lens 15 and the light pipe 10b.

  In the manufacturing method of the CCD solid-state imaging device 1B of the third embodiment, the interlayer insulating film 9 and the lower central portion of the microlens 14 are interposed between the interlayer insulating film forming process and the color filter forming process of the first embodiment. A light pipe forming step for forming a light pipe 10b that constitutes an optical waveguide that opens and opens upward in the center part in plan view of the light receiving unit 3, and condensing light from the microlens 14 on the light pipe 10b. And an intra-layer lens forming step for forming an inner lens 15 for further condensing the light. In the color filter forming step, the planarizing film 11 is disposed on the interlayer insulating film 9 and the inner lens 15. Thus, a color filter 12 having a predetermined color arrangement is formed corresponding to the position of each light receiving portion 3.

  FIG. 9A to FIG. 9E are main part longitudinal cross-sectional views for explaining a light pipe forming step in the manufacturing method of the CCD solid-state imaging device of FIG.

  In the light pipe forming step in the manufacturing method of the CCD solid-state imaging device 1B of the third embodiment having the above configuration, first, as shown in FIG. 9A, a photosensitive resist film is formed on the interlayer insulating film 9, A photosensitive resist film 23 (fourth resist film) is obtained by patterning the photosensitive resist film into a predetermined shape in a state where the side wall of the opening corresponding to the first light pipe forming position is tapered.

  Next, as shown in FIG. 9B, the interlayer insulating film 9 is formed together with the photosensitive resist film 23 in which the side wall of the opening is patterned to have a tapered section, and the sectional side tapered shape of the opening side wall of the photosensitive resist film 23 is formed. Is etched so as to be transferred to the interlayer insulating film 9, thereby forming a recess 9 b having a cross-sectional shape with the trapezoid turned upside down with respect to the interlayer insulating film 9.

  Subsequently, as shown in FIG. 9C, the transparent high refractive index material film 10A SiN film is embedded in the recess 9b of the interlayer insulating film 9, and the surface is flattened by etching back.

  Thereafter, as shown in FIG. 9D, a photosensitive resist film is formed on the interlayer insulating film 9 and the high-refractive index material film 10A as in the case of FIG. A photosensitive resist film 24 (fifth resist film) is obtained by patterning the photosensitive resist film into a predetermined shape in a state where the side wall of the opening corresponding to the formation position is tapered. Further, the high-refractive index material film 10A together with the photosensitive resist film 24 patterned in a tapered shape is etched so as to transfer the tapered shape of the side wall of the opening of the photosensitive resist film 23 to the interlayer insulating film 9, thereby providing a high refractive index. A recess having a cross-sectional shape with the trapezoid turned upside down is formed with respect to the rate material film 10A.

Further, as shown in FIG. 9E, the surface is flattened by embedding with a transparent SiO ₂ film 9a in the recess of the high refractive index material film 10A and etching back, so that two light pipes 10b on the left and right Can be formed. The SiO ₂ film 9 a is the same film material as the transparent SiO ₂ film constituting the interlayer insulating film 9.

  In short, this light pipe forming step is performed by tapering a cross-section taper on the side wall of the opening corresponding to the first light pipe forming position on the transparent interlayer insulating film 9 between the microlens 14 and the light receiving portion 3 by photolithography. A fourth resist film forming step of patterning the resist film into a predetermined shape with the shape added to obtain the fourth resist film 23, and etching the interlayer insulating film 9 together with the patterned fourth resist film 23 A taper shape on the side surface of the opening of the resist film 23 is transferred to the interlayer insulating film 9 to form a fourth recess that opens upward in a tapered shape; and a transparent high refractive index in the fourth recess The side wall of the opening corresponding to the second light pipe formation position on the high refractive index material film 10A and the interlayer insulating film 9 by the photolithography technique on the step of embedding with the material film 10A A fifth resist film forming step of obtaining a fifth resist film 24 by patterning the resist film into a predetermined shape with the cross-section tapered, and etching the high refractive index material film 10A together with the patterned fifth resist film 24 As a result, a taper shape on the side surface of the opening of the fifth resist film 24 is transferred to the high refractive index material film 10A to form a fifth recess that is opened upward in a tapered shape, and the inside of the fifth recess Is embedded in the same material as that of the interlayer insulating film 9 to form two light pipes 10b on the left and right.

  The intra-layer lens forming step in the manufacturing method of the CCD solid-state imaging device 1B of the third embodiment having the above-described configuration is performed on at least the light pipe 10b of the light pipe 10b and the interlayer insulating film 9 (or above the planarizing film). ) To form a high refractive index material film such as a SiN film, and a photosensitive resist film is formed on the high refractive index material film, and the amount of irradiation light is controlled using a transmittance gradation mask. Resist lens shape forming step of forming a photosensitive resist film into a lens shape under planar control, and simultaneously etching the lens-shaped photosensitive resist film and the high refractive index material film to form a lens of the photosensitive resist film A high-refractive-index material film lens shape forming step for forming the same high-refractive-index material film lens shape (intralayer lens 15) reflecting the shape.

  Alternatively, in this intra-layer lens forming step, a high refractive index material film such as a SiN film is formed on at least the light pipe 10b of the light pipe 10b and the interlayer insulating film 9 (or above the planarizing film). A high refractive index material film forming step, a resist film forming step of forming a photosensitive resist film on the high refractive index material film, and patterning the resist film into a predetermined shape by lithography technology, and reflowing the patterned resist film The resist lens shape forming process that forms an upward convex lens shape by the surface tension, and the same lens shape reflecting the lens shape of the resist film by simultaneously etching the lens-shaped resist film and the high refractive index material film A high refractive index material film lens shape forming step of forming a high refractive index material film.

  As described above, according to the third embodiment, by further providing the in-layer lens 15 between the microlens 14 and the light pipe 10b, the degree of freedom in the arrangement design of the microlens 14 is further increased, and the microlens 14 Need not be provided directly above the light receiving section 3. Further, the light condensing from the microlens 14 can be more reliably condensed on the center of the light receiving unit 3 via the inner lens 15 and the light pipe 10b.

  Further, in the two-pixel shared CCD solid-state imaging device 1B in which the positions of the light receiving portions 3 are periodically different, the light pipe 10b is inclined in a cross-sectional direction in accordance with the positions of the light receiving portions 3 periodically shifted in units of two pixels. The lower end surface portion of the light pipe 10b is opened above the central portion of the light receiving portion 3, and the upper end surface portion of the light pipe 10b is opened below the central portion of the microlens 14. Therefore, even if the positions of the light receiving units 3 adjacent to each other by sharing two pixels are periodically shifted, the light pipe 10b can be moved even when the positions of the light receiving unit 3 and the microlens 14 are shifted in plan view. As a result, the light can be guided to the light receiving unit 3 side and can be accurately and reliably condensed at the center position of each light receiving unit 3, and the light receiving sensitivity and shading can be further improved. In this case, the plurality of microlenses 14 and the upper end surfaces of the light pipes 10b corresponding to the plurality of microlenses 14 are all formed at equal intervals. As described above, since the microlens 14 and the upper end surface portion of the light pipe 10b are formed at equal intervals, it is possible to make the incident light amounts to the adjacent light receiving portions 3 close to each other by sharing two pixels. Thus, it is possible to eliminate variations in the amount of incident light at each light receiving unit 3.

  In the third embodiment, the inner lens 15 is further provided directly on the light pipe 10b. However, the present invention is not limited to this, and the inner lens 15 is further provided above the light pipe 10b via a planarizing film. Also good. The light pipe forming process of the third embodiment can also be used in the first and second embodiments. Further, the inner lens 15 may be provided on at least the light pipe 10b or above the interlayer insulating film 9 and the light pipe 10b.

  In the first to third embodiments, the two-pixel shared solid-state imaging device 1 or 1A or 1B having the respective light receiving units 3 that are periodically shifted from each other in units of two pixels has been described. 3 pixel sharing solid-state imaging device having light receiving portions 3 that are periodically offset from each other in units, and 4 pixel sharing having light receiving portions 3 that are periodically offset from each other in units of 4 pixels (in a planar view). Also for the solid-state imaging device, the light pipe 10 or 10a or 10b of the first to third embodiments can be applied, and the object of the present invention that can further improve the light receiving sensitivity and shading can be achieved. . In short, the light pipe 10 or 10a or 10b of the first to third embodiments can be applied to a solid-state image pickup device having a plurality of pixels and each of the light receiving units 3 that are periodically shifted from each other in units of a plurality of pixels. The object of the present invention that can further improve the light receiving sensitivity and shading can be achieved.

  In addition, although the case where the light pipe 10 or 10a or 10b of the first to third embodiments is applied to the CCD solid-state imaging device has been described, the present invention is not limited to this, and the light pipe 10 of the first and second embodiments is not limited thereto. Alternatively, 10a or 10b can be applied to a CMOS solid-state imaging device.

  In the CCD solid-state imaging device 1 or 1A or 10B, a light receiving unit 3 is provided as a photoelectric conversion unit for each pixel, and adjacent to the light receiving unit 3, a charge for transferring signal charges from the light receiving unit 3 in a predetermined direction. The transfer unit 4 and the gate electrode 6 for controlling the transfer of the read signal charges on the transfer unit 4 and the light shielding film 7 thereon are arranged. The light receiving unit 3 and the light receiving unit 3 above the opening 7a. An interlayer insulating film 9 is formed so as to fill the step with the light shielding film 7 opened at.

  On the other hand, in the CMOS solid-state imaging device, a light receiving unit is provided as a photoelectric conversion unit for each pixel, and adjacent to the light receiving unit, a charge transfer transistor for transferring signal charges from the light receiving unit to the charge voltage conversion unit, The signal charge transferred to the charge voltage conversion unit by the charge transfer transistor for each light receiving unit is voltage converted, amplified in accordance with the converted voltage, and read out as an imaging signal for each pixel unit An interlayer insulating film similar to the interlayer insulating film 9 is formed so as to cover the charge transfer transistors and the transistors constituting the readout circuit and the light receiving portion.

(Embodiment 4)
FIG. 5 is a block diagram illustrating a schematic configuration example of an electronic information device using the solid-state imaging device 1, 1 </ b> A, or 1 </ b> B of Embodiments 1 to 3 of the present invention as an imaging unit as Embodiment 4 of the present invention.

  In FIG. 5, the electronic information device 90 according to the third embodiment is a solid-state imaging device that obtains a color image signal by performing predetermined signal processing on the imaging signal from the solid-state imaging device 1 or 1A or 1B according to the first to third embodiments. 91, a memory unit 92 such as a recording medium that can record data after processing the color image signal from the solid-state image pickup device 91 for recording, and the color image signal from the solid-state image pickup device 91 for display The display unit 93 such as a liquid crystal display device which can be displayed on a display screen such as a liquid crystal display screen after the predetermined signal processing is performed, and the color image signal from the solid-state imaging device 91 is subjected to predetermined signal processing for communication. The communication unit 94 such as a transmission / reception device that can perform communication processing later, and the color image signal from the solid-state imaging device 91 can be subjected to printing processing after predetermined printing signal processing for printing. And an image output unit 95 such as a printer for. The electronic information device 90 is not limited to this, but in addition to the solid-state imaging device 91, at least one of a memory unit 92, a display unit 93, a communication unit 94, and an image output unit 95 such as a printer. You may have.

  As described above, the electronic information device 90 includes, for example, a digital camera such as a digital video camera and a digital still camera, an in-vehicle camera such as a surveillance camera, a door phone camera, and an in-vehicle rear surveillance camera, and a video phone camera. An electronic device having an image input device such as an image input camera, a scanner device, a facsimile device, a camera-equipped mobile phone device, and a portable terminal device (PDA) is conceivable.

  Therefore, according to the fourth embodiment, on the basis of the color image signal from the solid-state imaging device 91, the image is displayed on the display screen, or the image is output by the image output unit 95 on the paper. (Printing), communicating this as communication data in a wired or wireless manner, performing a predetermined data compression process in the memory unit 92 and storing it in a good manner, or performing various data processings satisfactorily Can do.

  As mentioned above, although this invention has been illustrated using preferable Embodiment 1-4 of this invention, this invention should not be limited and limited to this Embodiment 1-4. It is understood that the scope of the present invention should be construed only by the claims. It is understood that those skilled in the art can implement an equivalent range from the description of specific preferred embodiments 1 to 4 of the present invention based on the description of the present invention and the common general technical knowledge. Patents, patent applications, and documents cited herein should be incorporated by reference in their entirety, as if the contents themselves were specifically described herein. Understood.

  The present invention relates to a solid-state imaging device such as a CCD image sensor or a CMOS image sensor in which a plurality of light-receiving units that photoelectrically convert image light from a subject and image it, a manufacturing method thereof, and a solid-state imaging device. Electronic cameras such as digital video cameras and digital still cameras used as image input devices, such as digital video cameras and digital still cameras, image input cameras such as surveillance cameras, scanner devices, facsimile devices, television telephone devices, camera-equipped mobile phone devices, etc. In the field of information equipment, in a solid-state image sensor with multiple pixels sharing where the positions of the light receiving portions are periodically different, the light pipe is formed in a cross-sectional oblique direction according to the positions of the light receiving portions periodically shifted by the multiple pixel sharing The lower end of the light pipe is positioned above the center of the light receiving unit, and the microlens Since the upper end of the light pipe is open at the lower center, the positions of the adjacent light receiving portions that share multiple pixels are periodically shifted, and the planar view positions of the light receiving portion and the microlens are shifted. In addition, the light pipe can be accurately and reliably condensed at the center position of each light receiving unit, and the light receiving sensitivity and shading can be further improved. In this case, since the microlens and the upper end portion of the light pipe are formed at equal intervals, it is possible to make the incident light amount to each adjacent light receiving portion close to each other by sharing a plurality of pixels and to make each light receiving portion the same. Thus, variations in the amount of incident light can be eliminated.

DESCRIPTION OF SYMBOLS 1, 1A, 1B CCD solid-state image sensor 2 Semiconductor substrate 3 Light-receiving part 4 Charge transfer part 5 Gate insulating film 6 Gate electrode 7 Light-shielding film 7a Opening part 8 Insulating layer 9 Interlayer insulating film 9a SiO ₂ film 10, 10a, 10b Light pipe DESCRIPTION OF SYMBOLS 11, 13 Planarization film 12 Color filter 14 Micro lens 15 In-layer lens 21-24 Resist film 90 Electronic information equipment 91 Solid-state imaging device 92 Memory part 93 Display part 94 Communication part 95 Image output part

Claims (17)

A plurality of light receiving portions that photoelectrically convert incident light to generate signal charges are two-dimensionally arranged, and a plurality of microlenses that collect the incident light on each of the plurality of light receiving portions are the plurality of light receiving portions. In the solid-state imaging device disposed above the
A light pipe constituting an optical waveguide is formed in an interlayer insulating film between the microlens and the light receiving unit, the light pipe is formed in an oblique direction in cross section, and a lower end surface is flat at a position above the light receiving unit. The upper end surface is opened to include the central portion of the microlens in plan view at a position below the microlens, and the upper and lower end surface regions are viewed in plan view. Are different from each other ,
A solid-state imaging device in which the longitudinal cross-sectional shape of the light pipe is a parallelogram shape or an inverted right trapezoid shape .   In a solid-state image sensor sharing a plurality of pixels, where the planar view position of the light receiving unit is periodically different, the planar view position of the lower end surface of the light pipe according to the position of the light receiving unit periodically shifted in units of the plurality of pixels The solid-state imaging device according to claim 1, wherein the is positioned.   The solid-state imaging device according to claim 1, wherein the plurality of microlenses and upper end surfaces of the light pipes corresponding to the plurality of microlenses are all formed at equal intervals. _2. The solid-state imaging device according to claim 1, wherein a material of the light pipe is a high refractive index film such as a SiN film or a SiON film, and the interlayer insulating film is a SiO ₂ film.   2. The solid-state imaging device according to claim 1, wherein at least one of an upper end surface and a lower end surface of the light pipe is a circle, an ellipse, or a quadrangle including a square or a rectangle in a plan view.   The solid-state imaging device according to claim 1, wherein the upper and lower end surface regions are in an inclusive relationship with each other in a plan view or are shifted from each other in a plan view.   2. The solid-state imaging device according to claim 1, wherein an in-layer lens is provided on or above the light pipe for further condensing light from the microlens into the light pipe.   The light receiving unit is provided as a photoelectric conversion unit for each pixel, and adjacent to the light receiving unit, a charge transfer unit for transferring a signal charge from the light receiving unit in a predetermined direction, and read out thereon A gate electrode for controlling the charge transfer of the signal charge and a light shielding film disposed on the gate electrode, the light shielding film being opened above the light receiving portion, and forming a step between the light receiving portion and the light shielding film on the gate electrode. The solid-state imaging device according to claim 1, comprising a CCD solid-state imaging device in which the interlayer insulating film is formed so as to be embedded.   The light receiving unit is provided as a photoelectric conversion unit for each pixel, and adjacent to the light receiving unit, a charge transfer transistor for transferring signal charges from the light receiving unit to the charge voltage converting unit, and for each light receiving unit The signal charge transferred to the charge-voltage conversion unit by the charge transfer transistor is converted into a voltage, amplified in accordance with the converted voltage, and read out as an imaging signal for each pixel unit, The solid-state imaging device according to claim 1, comprising a charge transfer transistor and a transistor constituting a readout circuit, and a CMOS solid-state imaging device in which the interlayer insulating film is formed on the light receiving portion. A method of manufacturing a solid-state imaging device according to any one of claims 1 to 9
A light pipe that constitutes an optical waveguide that opens in a lower central portion of the microlens and opens upward in the center in a plan view of the light receiving portion in a transparent interlayer insulating film between the microlens and the light receiving portion. A method for manufacturing a solid-state imaging device having a light pipe forming step. It is a manufacturing method of the solid-state image sensing device according to claim 10 ,
A method of manufacturing a solid-state imaging device, further comprising an in-layer lens forming step of forming an in-layer lens on the light pipe for further condensing light from the microlens into the light pipe. It is a manufacturing method of the solid-state image sensing device according to claim 10 or 11 ,
The light pipe forming step includes:
A first resist film forming step of patterning the first resist film in a predetermined shape on the interlayer insulating film by a photolithography technique, and using the patterned first resist film as a mask, side surfaces of the interlayer insulating film are tapered. Etching to a predetermined depth so as to form a first recess that opens upward in a tapered shape, a step of filling the first recess with a transparent high refractive index film, and the first A second resist film forming step of patterning the second resist film into a predetermined shape by a photolithography technique so as to cover a part of the high refractive index film embedded in the concave portion, and using the patterned second resist film as a mask, A second recess forming step for forming a second recess in the high refractive index film by etching to a predetermined depth so that the side surface is tapered and opening the taper upward; and inside the second recess Method for manufacturing a solid-state imaging device and a embedding step of forming a cross-section parallelogram-shaped light pipe is embedded the same material as the material of the interlayer insulating film. It is a manufacturing method of the solid-state image sensing device according to claim 10 or 11 ,
The light pipe forming step includes:
A first resist film forming step of patterning the first resist film in a predetermined shape on the interlayer insulating film by a photolithography technique, and using the patterned first resist film as a mask, side surfaces of the interlayer insulating film are tapered. Etching to a predetermined depth so as to form a first recess that opens upward in a tapered shape, a step of filling the first recess with a transparent high refractive index film, and the first A third resist film forming step of patterning the third resist film into a predetermined shape by a photolithography technique so as to cover a part of the high refractive index film embedded in the recess, and using the patterned third resist film as a mask, Forming a third recess in the high-refractive index film by etching to a predetermined depth so that the side surface is vertically cut and opening vertically upward; Method for manufacturing a solid-state imaging device and a embedding step embeds the same material as Enmaku material cross section to form a light pipe opposite right-angled trapezoidal shape. It is a manufacturing method of the solid-state image sensing device according to claim 10 or 11 ,
The light pipe forming step includes:
A resist film is formed on the transparent interlayer insulating film between the microlens and the light-receiving portion in a state where the side wall of the opening corresponding to the first light pipe forming position is tapered by a photolithographic technique. Forming a fourth resist film by patterning into a shape; and etching the interlayer insulating film together with the patterned fourth resist film to form a tapered shape on the side surface of the opening of the fourth resist film. A fourth recess forming step of forming a fourth recess that is transferred to the interlayer insulating film and opened upward in a tapered shape; a step of filling the fourth recess with a transparent high refractive index material film; and the high refractive index material film On the interlayer insulating film, the resist film is patterned to a predetermined shape by a photolithographic technique with the side wall of the opening corresponding to the second light pipe formation position being tapered. A fifth resist film forming step of obtaining a fifth resist film by etching, and etching the high refractive index material film together with the patterned fifth resist film, thereby forming a tapered shape on the side surface of the opening of the fifth resist film Is transferred to the high-refractive-index material film to form a fifth recess that opens upward in a tapered shape, and the fifth recess is filled with the same material as the material of the interlayer insulating film. And a solid-state imaging device manufacturing method including an embedding step of forming two light pipes. It is a manufacturing method of the solid-state image sensing device according to claim 11 ,
The intra-layer lens forming step includes:
A high refractive index material film forming step of forming a high refractive index material film on or above at least the light pipe of the light pipe and the interlayer insulating film;
Forming a photosensitive resist film on the high-refractive index material film, and controlling the amount of irradiation light using a transmittance gradation mask to form the photosensitive resist film into a lens shape. Process,
The high refractive index formed in the lens shape of the same high refractive index material film reflecting the lens shape of the photosensitive resist film by simultaneously etching the photosensitive resist film of the lens shape and the high refractive index material film A method for manufacturing a solid-state imaging device, comprising a material film lens shape forming step. It is a manufacturing method of the solid-state image sensing device according to claim 11 ,
The intra-layer lens forming step includes:
A high refractive index material film forming step of forming a high refractive index material film on or above at least the light pipe of the light pipe and the interlayer insulating film;
Forming a photosensitive resist film on the high refractive index material film, and patterning the resist film into a predetermined shape by a lithography technique;
A resist lens shape forming step of reflowing the patterned resist film to form a convex lens shape by its surface tension;
A solid-state imaging comprising: a lens shape forming step of simultaneously etching the lens-shaped resist film and the high refractive index material film to form the high refractive index material film having the same lens shape reflecting the lens shape of the resist film Device manufacturing method. Electronic information device using the imaging unit the solid-state imaging device according to any one of claims 1 to 9 as an image input device.

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